If he doesn't repair the door and its left to USPS to do so, they will take the cost out of the rent.
Eventually, when maintenance costs rise high enough, and USPS needs more money for repairs than they would ever pay in rent, they have options ~ (1) Seize the building, (2) Move somewhere else, (3) Drag the landlord through the courts almost eternally.
Sounds like the landlord best get that door repaired.
You assume the landlord knows of the problem.
My post office is owned by someone in California. I’m in Missouri. We NEED some concrete repair, but we GOT an ADA compliant bathroom. We had to shut down the bathroom for about six weeks, put up with all the noise and dust from the part-time contractors, and we finally are ADA compliant, down to the wheelchair accessible water fountain.
There are no handicapped employees in our office, no public access to the bathrooms, and we’re required to be physically capable enough to lift 75 lbs out of the bottom of our parcel hampers. What the hell do we need an ADA compliant bathroom for?